Verification Email no link code showing when adding new users

question on this part for /wp-admin/user-new.php

function admin_created_user_email( $text ) {
	return sprintf( __( "Hi,
You've been invited to join '%s' at
%s as a %s.<br />
If you do not want to join this blog please ignore
this email. This invitation will expire in a few days.</p>
<p>Please click the following link to activate your user account:
%%s" ), get_bloginfo('name'), site_url(), wp_specialchars( $_REQUEST[ 'role' ] ) );
}

when my members tried to add new user to their admin panel, the email sent to the user has no verification link code.

what do you think should I do to fix this porblem thanks